There is conventionally known a fixing device provided with a heater disposed in an internal space of a tubular member and a frame supporting the tubular body (see JP2009-180839, for example). In this fixing device disclosed in this reference, the tubular body has an end opening (an opening formed in an end portion of the tubular body) such that the heater is inserted into the internal space of the tubular body through the end opening. The tubular body is thus heated from inside by heat of the heater.
The heater is connected to a terminal fixed to the frame. Specifically, the heater is connected to a pin connected to the terminal. The heater is configured to generate heat upon receipt of power from the terminal via the pin.